WordPress Multisite Installation:
"Your plugins are all up to date." I get that message on the update-core.php site, even so I'm certain that this is not the case. My plugins are not all up to date. The same with themes and with the WordPress Core itself. I've had this problem for a while, so I manually updated to 3.3.1 recently to see if that fixes the problem.
It worked fine up untill December 2011 or so. Before updating to 3.3.1, I saw a "HTTP Timeout" Error on the Dashboard where the WordPress Blog Feeds are. After updating to 3.3.1 this error is gone. At this forums I saw people suggesting editing core files to increase the timeout limit, but that is no optimal solution.
I'm unsure if the problem is on my side, maybe WordPress API Servers have problems? Heard somthing about them being updated.
A different installation (no multisite) on another server does not have this problem.